@article{NUMA_1987__52_5_133252,
     author = {R. Rannacher and H. Blum},
     title = {Extrapolation {Techniques} for {Reducing} the {Pollution} {Effect} of {Reentrant} {Corners} in the {Finite} {Element} {Method.}},
     journal = {Numerische Mathematik},
     pages = {539--564},
     publisher = {mathdoc},
     volume = {52},
     number = {5},
     year = {1987},
     zbl = {0649.65060},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1987__52_5_133252/}
}